Primary electric clock



(No Model.)

D. P. SWEET.

PRIMARY ELECTRIC CLOCK. No. 284,578. Patented Sept. 4, 1888.

, EEWIIIEM 1 lnnw' mlmm 77 2%: emrea. J72 Why? LNITED STATES PATENT OFFICE.

D. FRED SWEET, OF HASTINGS, MICHIGAN.

PRIMARY ELECTRIC CLOCK.

SPECXFICATION forming part of Letters Patent No. 284,578, dated September 4, 1883,

Application tiled April 14, 1888.

To aZZ whom it may concern.-

Be it known that I, l). FRED SWEET, a citizen of the United States, residing at Hastings, in the county of Barry and State of Michigan, have invented certain new and useful Improvements in Primary Electric Clocks, of which the following is a specification, refer ence being had therein to the accompanying drawings.

This invention relates to certain improve ments in primary electric clocks and transmitters; and it has for its objects, fnst, to so construct the escapement-wheel that it will skip a tooth during its rotation, leaving the clock-movement free to overcomethe resistance of the circuit making and breaking spring; second, to give distance of motion suflieient to insure perfect contact and prevent a double make and break by the escapement-wheel being moved back by the motion of the pendulum; third, to provide for a second skip of the escapement-wheel, so as to give a good and quick clearance when the circuit is opened; and, fourth, to provide for the employment of a light battery in connection with the primary clock, in a local circuit, to operate an electro magnet, and a secondary circuit maker and breaker to send thenecessary impulses through the line-circuit, thereby reducing the spark at the contact maker and breaker of the primary clock, and the consequent injury at such points. These objects I attain by the means illustrated in the accompanying drawings, in which- Figure 1 represents a front elevation of my improved primary clock and transmitter; Fig.

2, a horizontal sectional View on the line mm of Fig. 1; Fig. 3, a back view of the escapementwheel detached; Fig. 4, a perspective view of the escapementpallets. Fig. 5 represents an edge view of aportion of the apparatus, showing the three fingered contact maker and breaker.

The letter A indicates the frame of the clock, and B the escapement-wheel, which has two notches or teeth removed, as indicated by the letters I) c, and at one side of said removed teeth, the wheel has secured to it two teeth, (I e. The main movements of the clock are of the ordinary or any approved description, and drive the pallet-lever O, which is mounted in the usual manner, and has secured to it the penduluni-actuating rod E, as shown in Fig.

(X0 model.)

1. The upper pallet, c, is double the width of the lower pallet, c, for the purpose more fully hereinafter described. The escapementwheel, 011 its outer face, near the center, is provided with a projection, the object of which is to lift and drop the contact-making spring F. which is secured to a post, G, attached to an extension, G, fastened to the frame of the clockwork. Below said spring sits one end of a metallic arm, also secured to said extension, which serves as a stop to limit the downward movement of the spring.

The letter H indicates a contact-point secured to the lower end of a set-screw passing through a bracket, I, which is secured by an insulatirig-connection to the extension G, be fore mentioned. The said spring and contactpoint serve to make and break an electric circuit through the wires K and L, secured at their ends, respectively, to the extension and bracket before mentioned, the battery M having its poles connected with said wire and the helices of an electro-magnet, N, as shown in Fig. 1 of the drawings.

The letter F indicates the armature of the said magnet, which is pivoted at one end to a post, R, secured to the supporting-wall S of the clock in such position that said armature may vibrate freely over the poles of said magnet. The said armature is held normally away from the magnet by means of a coiled spring setting around the post and secured to it at one end, the other end of said spring be ing formed with aright-angled bend, T, which is clamped to a transmitting contact maker and breaker and the armature by means of a screw, T, so as toform a perfect electrical connection. The said contact maker and breaker consists of a bent metallic plate, U, which is formed with a series of spring; fingers, V. Between said contact maker and breaker and the armature extends a metallic post, \V, which is secured to the supportingwall of the clock. The distance between the said contact maker and breaker and the armaat such point when the armature is in a normal position. The post to which the armature is pivoted is connected with one end of a wire, X, forming part of a secondary or line circuit, and the post V with a wire, Y, forming part of the same circuit, in which is included any desired number of secondary clocks and a battery powerful enough to give the impulses to the same.

It will appear that by the above-mentioned construction, the escapement wheel having two teeth taken out and set off at one side and the pallets formed of unequal widths, the wheel will be permittedto skip a tooth at one point in its revolutionthat is, as the pin Z is passing the contact making and breaking spring Fleaving the clock-movement free to overcomethe resistance of the circuit make and break spring, and also to get suii icient distance soon be interrupted.

of motion to insure perfect contact and prevent a double make and break by the backward movement of the escapement, which is caused by the excess of motion of the pendulum. It will also be perceived that directly after the first skip a second skip of the wheel is permitted, which gives a free and rapid clearance when the circuit is to be opened.

The primary circuit maker and breaker is to be used in a local circuit of its own, as indicated, the object being to enable the use of a very light battery, thereby obviating the heavy spark attendant upon the employment of a heavy battery, which would soon injure the contacts.

The three fingers of the secondary circuit maker and breaker insure the proper contact in the main or line circuit, in which a large battery has necessarily to be employed, according to the number of secondary clocks in the line. With such battery in the circuit a very large spark would be produced with a single contactmake and break, which would soon oxidize the contacts s'o that the circuit would As constructed, however, the fingers of the secondary contact maker and breaker, when brought into contact with the post, are pressed against it with a rubbing motion, the-fingers varying slightly in their horizontal planes. As the current is broken by the last portion of the contacts, the

circuit will be broken by the finger that last leaves the post, so'that when one contact becomes oxidized the other two are unafiected, and the contact will be made by the next in turn, and when that becomes oxidized the contact will be made by the third, thus permitting the first finger, by the rubbing action, to clear ofi" the oxidation and make the circuit anew when the other contacts become oxidized, thus enabling the contact maker and breaker to antomatically regulate itself, so as to insure a perfect make and break for an indefinite time.

The operation of my invention is as follows: The primary clock being put in motion, at

"each revolution of the escapement-wheel the spring will be lifted by the pin Z touching the contact-maker F and establishing a current through the wires A, battery M, and the helices of the magnet T. This attracts the armature, so that the spring U comes in contact with the post WV, establishing a current through the line-wires X Y and the secondary clocks and a battery of suitable power.

Having thus described my invention, what I claim, and desire to secure by Letters Patent,

1. The combination, in a primary electric clock, of the escapement-wheel having two of the teeth cut away and offset teeth at one side, and the pallet-lever having pallets of unequal width, whereby the escapement-wheel is permitted to skip during its revolution, substantially as and for the purposes specified. I 2. The combination, with the escapementwheel having two "of the teeth cut away and the pallet lever having pallets of unequal width, of the projection .on the escapementwheel, the spring contact maker and breaker, the contact-point, and the circuit-wires con nected with a suitable battery, and an electromagnet adapted to operate a secondary circuit maker and breaker, substantially as and for the purposes specified.

In testimony whereof I afiix my signature in presence of two witnesses.

D. FRED SWEET. Witnesses:

GEORGE CURRY, F. HoToHKIss. 

